The-Computer-for-the-21st-Century-(ppt课件)

TheComputerforthe21stCenturyMarkWeiserScientificAmerican,September199122Introduction“Themostprofoundtechnologiesarethosethatdisappear.Theyweavethemselvesintothefabricofeverydaylifeuntiltheyareindistinguishablefromit.”33IntroductionƒMarkWeiseroftenreferredtoasthefatherofubiquitouscomputingƒCoinedthetermin198844FirstInformationTechnologyƒWritingasanexample,ƒAbilitytorepresentspokenlanguageƒLongtermstorageofinformationƒUbiquitousinindustrializednationsƒWhereisit?ƒBooks,magazines,streetsigns,billboards,candywrappersƒConstantbackgroundpresenceofthis“literarytechnology”doesnotrequireactiveattentionƒInformationtobetransmittedisreadyataglance55ComputersToday(1998)“Approachableonlythroughcomplexjargonthathasnothingtodowiththetaskforwhichpeopleusecomputers…analogoustotheperiodwhenscribeshadtoknowasmuchaboutmakinginkorbakingclayastheydidaboutwriting”66ComputersToday(1998)ƒNotjustauserinterfaceproblemƒNeedanewwayofthinkingaboutcomputersƒTakeintoaccountthehumanworldƒVanishintothebackgroundƒDisappearanceduetohumanpsychologynottechnologyƒCompiling,tacitdimension,visualinvariants,horizon,ready-to-hand,periphery77UbiquitousComputingƒUbiquitousComputing≠VirtualRealityƒMakesaworldinsidethecomputerƒExcludesdesks,office,trees,weatherƒEmbodiedVirtualityƒBringingcomputer-readabledataintothephysicalworldƒLocationƒComputermustknowwhereitisƒAdaptbehaviorƒScaleƒSuitedforaparticulartask99ArtifactsƒTabsƒInch-scalemachinesƒInterconnectedƒTakeonfunctionthatcomputersdon’tƒActivebadgeƒPadsƒFoot-scalemachinesƒIntendedtobe“scrapcomputers”ƒBoardsƒYard-scalemachinesƒVideoscreens,whiteboards,flipcharts,bulletinboards,electronicbookcase1010TechnologyRequirementsƒTechnologyforubiquitouscomputingmustbeƒCheapƒLowpowercomputerthatincludeconvenientdisplaysƒSoftwareforapplicationsandanetworkthattieseverythingtogetherƒSocialissuesƒPrivacy1111ConclusionƒUbiquitouscomputerswillhelpovercomeinformationoverloadƒChangeviewpointƒMovecomputersinhumanenvironmentƒMakeinteractionmoreenjoyable“Thereismoreinformationavailableatourfingertipsduringawalkinthewoodsthaninanycomputersystem,yetpeoplefineawalkamongtreesrelaxingandcomputersfrustrating.”TheComingofAgeofCalmTechnologyMarkWeiserandJohnSeelyBrownBeyondCalculation(Book),19971313Introduction“Theimportantwavesoftechnologicalchangearethosethatfundamentallyaltertheplaceoftechnologyinourlives.Whatmattersisnottechnologyitself,butitsrelationshiptous.”1414IntroductionƒTwogreattrendsoverthelast50yearsƒMainframeƒPCƒInternetcarryingusthroughaneraofdistributedcomputingƒBridgetoubiquitouscomputingTheMajorTrendsinComputingMainframeManypeopleshareacomputerPersonalComputerOnecomputer,onepersonInternet–DistributedComputing…transitionsto…UbiquitousComputingManycomputersshareeachofus1515UCERAƒPhase3–UCERAƒ2005–2030ƒLotsofcomputerssharingeachofusƒCharacterizedbytheconnectionofthingsintheworldwithcomputationM.Weiser.“BuildingInvisibleInterfaces,UIST,1994.1616HarbingersoftheUCEraƒEasytofind40µCinamiddle-classhomeintheUSƒAlarmclocksƒMicrowaveƒTVremotecontrolƒToysƒManymoreƒDonotqualifyasUCƒMostlyusedoneatatimeƒMasqueradingasold-styledevicesƒTiedevicestointernetƒConnectmillionsofinformationsourceswithhundredsofinformationdeliverysystemsinyourhouse1717CalmTechnologyƒMostpotentiallyinteresting,challengingchangedimpliedbyubiquitouscomputingisafocusoncalmƒComputersareallaroundƒStayoutofthewayƒDesignedsopeoplebeingsharedbythecomputersremainsereneandincontrolƒDifferencewillbeinhowtheyengageourattentionƒMovesbetweencenterandperipheryofourattention1818ThePeripheryƒAttunedtowithoutattendingtoexplicitlyƒWhendrivingattentioncenteredonroad,radio,passenger,butnotnoiseoftheengineƒUnusualnoisenoticedimmediately,andcouldquicklyattendtoitƒCalmtechnologymoveeasilyfromperipherytocenterofattentionandbackƒInformingwithoutburdeningƒAbletohandlemoreinformation(thenifeverythingatcenter)ƒUsertakescontrol1919ExamplesofCalmTechnologyƒInnerOfficeWindowsƒEnhancesperipheralreachandlocatednessƒExtendsperipherybycreatingtwowaychannelforcluesaboutenvironmentƒConnectwiththoseoutsidetheofficeƒIllustratefundamentalpropertyofmotionbetweencenterandperiphery2020ExamplesofCalmTechnologyƒDanglingStringƒ8footpieceofplasticspaghettithathangsfromsmallelectricmotormountedonceilingƒConnectedtonearbyEthernetcablesothateachbitofinformationthatgoespastcausestinytwitchofthemotorƒProvidesbackgroundofdataweatherƒBusynetwork–whirlingstringƒQuitenetwork–smalltwitchƒPlacedinunusedcornerofahallwayƒNewcenterofattentionbybeinguniqueƒBecomesperipheralasgentlemovementbecomesbackgroundƒStringseenandhearandincreasesperipheralattunement2121ConclusionƒContradictorystatementƒFrequentcomplainofinformationoverloadƒMoreinformationcouldbeencalmingƒDesigningintheeraofubiquitouscomputingƒTobecomeattunedtomoreinformation,needtoattendtoitlessƒTakeintoaccountcenterandperipherytoachieveincreasedsenseoflocatednessPervasiveComputing:VisionsandChallengesM.SatyanarayananIEEEPersonalCommunications,August20012323IntroductionƒTechnologyneededtoimplementWiesernot